Cut, Copy & Paste the ColdFusion PageContext Buffer

I've been messing about with some localisation stuff lately and I wanted a way to intercept the ColdFusion output buffer so I could mess with it.

Now I know you can sort of use <CFSAVECONTENT> for that. But it's mildy irritating since it only lets you use it on a single page. You can’t (for example) start it on one template and end it on another. Tsk!

So what I needed was a solution. After much poking things with sticks (metaphorical sticks) I found the answer I was looking for.

I’ve knocked up a CFC that gives the ability to manipulate the contents of the output buffer of ColdFusion exposing the following methods: -

• Cut(item) – Write the buffer contents to variable named item and clear the buffer.
• Copy(item) – Write the buffer contents to variable named item.
• Paste(item) – Past the contents of variable named item into the buffer.
• Get(item) – Get the contents of variable named item
• Put(item) – Update the contents of variable named item
• Clear() – Clear the buffer.

Here’s the code: -

Buffer.cfc

<cfcomponent name="buffer" hint="Tools for messing with the ColdFusion string buffer"> <cffunction name="init" hint="I initialise the cfc"> <cfset this.capturedBuffers=structNew()> <cfreturn this> </cffunction> <cffunction name="copy" hint="Copy contents of the buffer to the named item"> <Cfargument name="target" type="string" default="clipboard" hint="Item to copy to. Default is clipboard."> <cfset tmpBuffer=GetPageContext().getOut().getBuffer().toString()> <cfset this.capturedBuffers[arguments.target]=duplicate(tmpBuffer)> </cffunction> <cffunction name="paste" hint="Paste the selected buffer item to the output stream"> <Cfargument name="source" type="string" default="clipboard"> <cfoutput>#this.capturedBuffers[arguments.source]#</cfoutput> </cffunction> <cffunction name="cut" hint="Cut contents of the buffer to the named item"> <Cfargument name="target" type="string" default="clipboard"> <cfset tmpBuffer=GetPageContext().getOut().getBuffer().toString()> <cfset this.capturedBuffers[arguments.target]=duplicate(tmpBuffer)> <cfset this.clear()> </cffunction> <cffunction name="get" hint="Returns the contents of the named buffer item"> <Cfargument name="source" type="string" default="clipboard"> <cfreturn this.capturedBuffers[arguments.source]> </cffunction> <cffunction name="put" hint="Overwrites the contents of the named buffer item"> <Cfargument name="content" type="string" default="" required=true> <Cfargument name="target" type="string" default="clipboard"> <cfset this.capturedBuffers[arguments.target]=arguments.content> </cffunction> <cffunction name="clear" hint="Resets the buffer"> <Cfcontent reset="yes"> </cffunction> </cfcomponent>

So, how do I use this buffer.cfc thing? - Here’s an example

<!--- create the cfc ---> <cfset bufferObj=createObject("component","buffer").init()> <!--- clear the buffer ---> <cfset bufferObj.clear()> <!--- output some text ---> Lorem ipsum dolor sit amet, consectetuer adipiscing elit. <!--- cut the text from the output buffer ---> <cfset bufferObj.cut("firstBit")> <!--- output some more text ---> Lorem Ipsum is simply dummy text of the printing and typesetting industry. <!--- cut the text from the output buffer ---> <cfset bufferObj.cut("secondBit")> <!--- Retrieve the "secondBit" from the cfc, bold all the e characters, update the cfc data---> <cfset tmpText=bufferObj.get("secondBit")> <cfset tmpTextp=replace(tmpText,"e","<strong>e</strong>","all")> <cfset bufferObj.put(tmpText,"secondBit")> <!--- Paste secondBit and firstBit back into the stream - but in reverse order ---> <cfset bufferObj.paste("secondBit")> <cfset bufferObj.paste("firstBit")>